My U.S. Pat. No. 4,153,287 for Shovel Blade, issued May 8, 1979 discloses a snow shovel having an attached brush with semirigid bristles projecting from the lower surface of the shovel blade. The patent discloses that the semirigid bristles can serve as ice choppers when the shovel is wielded vertically against ice on the surface to be cleared.
Two additional patents in the prior art disclose shovels particularly useful for chopping ice. In U.S. Pat. No. 1,124,046 of Lopez et al, ax blades are fixed upon the upper surface of a shovels blade using bolts which pass through holes in both the ax blade and the shovel blade. In U.S. Pat. No. 2,102,133 of Schoenberger, an ax bit in the form of a sleeve is placed over the rear corner of the shovel blade and secured by a pressure fit, precluding the need for holes in the shovel blade.
At times a rigid ice chopper is more effective in chopping ice than are the semirigid bristles of the brush in U.S. Pat. No. 4,153,287. However, addition of independently attached ax blades or bits as shown in U.S. Pat. Nos. 1,124,046 and 2,102,133 to the shovel blade of U.S. Pat. No. 4,153,287 would be undesirable for several reasons. Use of the ax blade in Pat. No. 1,124,046 would necessitate additional holes to be drilled in the shovel blade. Use of the ax bits in Pat. 2,102,133 would require additional separate fasteners. Furthermore, the ax bits and the clamps (shown in FIG. 5 of Pat. 4,153,287) would both project from the sides of the shovel blade at different positions.
Use of the ax blades or bits for chopping ice requires rotation of the shovel blade 90 degrees around the axis of the handle. Chopping is accomplished by raising and lowering the shovel blade through a wide range of chopping angles for impacting the cutting edge with the surface to be cleared. If both ax bits and brush clamps project from the sides of the shovel blade at different positions, the wielding of the shovel blade for chopping ice on the surface to be cleared is restricted to a limited range of chopping angles within which the clamps are not impacted against the surface. If the clamps are impacted, they may undergo damage and may loosen their grip on the brush and shovel blade.